What causes swelling during late pregnancy?

When a woman becomes pregnant, she will experience varying degrees of edema sooner or later, depending on her physical condition, usually concentrated in the hands and feet. Because of the abnormal conditions that occur in the pregnant woman's body during pregnancy, parents are very worried about the impact on the child, so they are very concerned about the cause of edema in the late pregnancy. So, what is the cause of edema in late pregnancy? Let’s take a closer look below.

1. After pregnancy, blood volume begins to increase gradually from 6 weeks, reaches a peak at 34 weeks, and remains at this level until two weeks after delivery, when it returns to pre-pregnancy levels. Blood volume can increase by about 40% compared to the non-pregnant period, so as blood volume increases, interstitial fluid will also increase.

2. Because when blood increases, the increase in plasma is greater than the increase in blood cells, etc., the blood components will be relatively diluted, and the relative concentration of plasma albumin will be lower than that in the non-pregnant period. Plasma albumin is the main component that maintains plasma osmotic pressure. Plasma osmolality is lower during pregnancy than during non-pregnancy. This makes it easy for water in the blood to penetrate into the interstitial fluid, causing lower limb edema.

3. After pregnancy, the uterus enlarges, which increases the pressure in the pelvis, thereby affecting the venous blood flow in the lower limbs. This is also one of the important reasons for lower limb edema. If the swelling during pregnancy is relieved after rest or sleep, it is physiological and there is no need to worry.

Edema will become more severe as the pregnancy progresses.

As the number of weeks of pregnancy increases, edema in pregnant women will become increasingly obvious. During the entire pregnancy, body fluid increases by 6-8 liters, of which 4-6 liters are extracellular fluid, which is stored in tissues and causes edema.

This phenomenon is quite common during pregnancy. The soles of the feet, ankles, and calves are the most common areas where edema occurs, and sometimes even the face may experience slight swelling. The closer to the due date, the more severe the swelling will be. If it is hot, the swelling will be more obvious.

Mild swelling is normal, but if it is accompanied by high blood pressure and proteinuria, the expectant mother is at risk of developing gestational hypertension and must undergo prenatal examinations and fully cooperate with the doctor.

The above is an introduction to the causes of edema in late pregnancy. I hope it will be helpful to everyone’s understanding. Edema in the late pregnancy is a problem that many women will experience. When it happens, don't be too nervous. The key is to pay attention to your daily life and work, don't stand or sit for long periods of time, and eat more high-protein foods and vegetables. The symptoms can be significantly improved.